textproduct: Quad Cities

KEY MESSAGES

- There is an Enhanced Risk/Level 3 of 5 for severe weather today, with damaging wind and tornadoes the primary risks. The risk for a few strong/significant tornadoes is increasing. - Very fast storm motions between 50-60 mph will offer significantly less time to act this afternoon and evening, thus it's very important to stay weather aware!

- There is an Enhanced/Slight Risk (level 2+3 of 5) for severe weather Friday, with all modes of severe weather possible.

- Cooler and drying out this weekend, with frost/freeze potential early next week.

SHORT TERM /THROUGH TONIGHT/

Issued at 238 PM CDT Thu Apr 2 2026

A very active afternoon/evening is expected with numerous severe storms possible. Stay weather aware and be quick to react when a warning is issued as storms will be moving VERY fast! This will greatly reduce your time to take action so seek shelter immediately!

Water vapor imagery early this afternoon shows well defined negatively tilted shortwave lifting northeast over southwest IA with a dry slot moving into our southwest CWA. 18z surface observations and analysis have a 999mb surface low out ahead of the main upper wave just south of DSM and a warm front extending east of the low right along I-80 towards DVN. GOES Day Cloud Phase RGB imagery has a nice area of clearing from a line from IOW-EOK and points west. A Tornado Watch has been recently issued until 8pm for the entire CWA.

Severe Risk

The question initially with storm development today was how much clearing/destabilization was going to take place. The aforementioned warm front was taking its time lifting north this morning, but the low has now surged it towards the I-80 corridor with building 0-1km and SBCAPE expected this afternoon out ahead of the storms. In addition, a very strong kinematic and moist environment is in place as shown on our 18z sounding (winds over 40kts for most of the column, sickle shaped hodograph, and 1.39 PW). At the same time, a mid-level speed max around 60kts is developing just ahead of the storms which is one of the key composites to significant tornado environments in the DVN CWA as well as surging northward dewpoint/CAPE gradients. All this being said, numerous severe storms will be possible with discrete supercells initially capable of quickly becoming tornadic. Some concern for a few significant tornadoes (EF2+) is there as well with such strong 0-1km SRH values over 300 m2/s2 and some low level backing of winds especially for any supercell that cross the warm front.

This is still one failure mode that I do want to point out and that is with so much shear aloft, updrafts could easily become disrupted/ripped apart thereby limiting the overall severe risk. Sometimes too much shear is a good thing for reducing the severe threat.

Winds have underperformed so far today in the advisory area, but some gusts near 45 mph is still possible this afternoon. Have decided to continue the advisory for now but may be able to be cancelled early this evening.

LONG TERM /FRIDAY THROUGH THURSDAY/

Issued at 238 PM CDT Thu Apr 2 2026

Another active day with severe weather is expected late Friday afternoon through early Saturday, as a closed low moves over the northern Plains. There are some similar aspects to today's system, but with 12z models continuing to show a later time of day and bit further west and north surface low track, this favors storm initiation over western and central IA late Friday afternoon/early evening. This activity would then likely evolve into a mature squall line or QLCS and move east into the CWA during the evening, exiting early Saturday. Timing of severe weather would be after 7 PM Saturday with this line. This setup looks to largely favor damaging winds with some significant wind potential, and a few tornadoes with any mesovortices. However, will still have to keep tabs for some discrete cell potential in the warm sector and in close proximity to the warm front. It will another day of mesoscale forecasting and monitoring the evolution of the front/destabilization of the boundary layer/EML capping. There is some potential for more slowing of this system thereby reducing the overall severe threat in the evening as instability wanes. SPC has maintained an Enhanced/Slight Risk (level 2+3 of 5) for severe weather for areas west of a Clinton IA to Galesburg IL line.

Saturday will see conditions begin to dry out and turn cooler as high pressure begins to build in.

Sunday-Tuesday...Continued cooler and more seasonable this stretch into early next week, with a return flow induced precip event possible some time Tue into next Wed. There will also be a concern for frost/freeze potential each morning through the period due to recent greenup that will need to be evaluated in later forecasts.

AVIATION /00Z TAFS THROUGH 00Z SATURDAY/

Issued at 624 PM CDT Thu Apr 2 2026

Things are starting to calm down at the start of this period as the line of storms is already pushing east of the MS River. The biggest issue for tonight will be determining just how low stratus will and what's the potential for fog late tonight. This will be a setup where dense fog will likely develop where we see stratus clear out as a surface ridge axis moves in by sunrise Friday. Right now, the HRRR and RAP show the stratus winning out tonight, with fog being more spotty and really a thing where the stratus deck eventually find its way to the ground where fog develops. LAMP guidance has been slowly pulling back from the fog as well, so started to back away from the fog some, but still left some potential in place that we had from the 18z TAFs. For the rest of Friday, the DVN area will be north of a warm front surging north across MO/IL, so it's likely that the stratus will be stubborn to clear out of eastern IA. This period will end with an increasing shra risk north of the warm front, though it's just after this period in the 00z to 06z Saturday window where the TSRA potential will really ramp up, so something that the 6z TAFs will have to tackle.

DVN WATCHES/WARNINGS/ADVISORIES

IA...None. IL...None. MO...None.